Santon reversing switch. (Used on some Myford Lathes.)
Information on Santon switch which is sometimes fitted to Myford lathes
This is how I understand the switch works.
Forward B to 2, C to 1, A to 3
Middle / off position There should be no continuity between any pairs of terminals on the swich.
Reverse B to 2, C to 3, A to 1
The switch is made up of 5 contact sets. Each contact set is on a layer of the switch. I will call the front layer layer 1.
Terminals C, 3, and A are actually connected to 2 layers each. (You can see the metal connections from 2 adjacent layers bent together.)
Terminal C goes to layers 1 & 2.
Terminal 3 goes to layers 2 & 3.
Terminal A goes to layers 3 & 4.
There is also a wire link from an unmarked terminal on layer 1 to terminal 1
Layer 1 Terminals C (and 1 via a wire link) (Closed in forward.)
Layer 2 Terminals C & 3 (Closed in reverse.)
Layer 3 Terminals A & 3 (Closed in forward.)
Layer 4 Terminals A & 1 (Closed in reverse.)
Layer 5 Terminals 2 & B (Closed in forward & reverse.)
Terminals 1, 3, A, & C form a double pole double throw switch which is used to reverse the connections to the start winding.
Terminals 2 & B apply the live feed to one side of the run winding when the switch is in the forward or reverse position.
The other side of the run winding is permanently connected to neutral.
Stanton reversing switch connections.
1 To motor start terminal (R ?)
2 Live in
3 To motor start terminal (S ?)
A Live in
B To motor run terminal (U2 ?)
C | Neutral in &
| To motor run terminal (U1 ?)
The motor terminal may be labelled as in the brackets but many different motors are used with different markings
This is how I understand the switch works.
Forward B to 2, C to 1, A to 3
Middle / off position There should be no continuity between any pairs of terminals on the swich.
Reverse B to 2, C to 3, A to 1
The switch is made up of 5 contact sets. Each contact set is on a layer of the switch. I will call the front layer layer 1.
Terminals C, 3, and A are actually connected to 2 layers each. (You can see the metal connections from 2 adjacent layers bent together.)
Terminal C goes to layers 1 & 2.
Terminal 3 goes to layers 2 & 3.
Terminal A goes to layers 3 & 4.
There is also a wire link from an unmarked terminal on layer 1 to terminal 1
Layer 1 Terminals C (and 1 via a wire link) (Closed in forward.)
Layer 2 Terminals C & 3 (Closed in reverse.)
Layer 3 Terminals A & 3 (Closed in forward.)
Layer 4 Terminals A & 1 (Closed in reverse.)
Layer 5 Terminals 2 & B (Closed in forward & reverse.)
Terminals 1, 3, A, & C form a double pole double throw switch which is used to reverse the connections to the start winding.
Terminals 2 & B apply the live feed to one side of the run winding when the switch is in the forward or reverse position.
The other side of the run winding is permanently connected to neutral.
Stanton reversing switch connections.
1 To motor start terminal (R ?)
2 Live in
3 To motor start terminal (S ?)
A Live in
B To motor run terminal (U2 ?)
C | Neutral in &
| To motor run terminal (U1 ?)
The motor terminal may be labelled as in the brackets but many different motors are used with different markings
Diagram of Santon switch
Do not assume that the switch you have has the same connections as this one. Check with a multimeter that they are the same